Method for precision low stress coring and slicing of apples and other soft-cored or pitted fruits

ABSTRACT

Fruit items are positioned between vertical pins located in the calyx and stem hole of said fruit item, thereby securing the fruit item by a compressive force through its core. A core tube surrounding the upper pin descends to meet the lower pin, thereby completely piercing the fruit item and isolating its core inside the tube. A cushioned ram pushes the edible portion of the fruit item down over the core tube, through a cassette of radial knives, creating a plurality of wedges that fall immediately into an enzyme bath. The bath seals freshness into the fruit item&#39;s cell structure by preventing contact with oxygen. The solid core is ejected and the edible outside portion of the fruit item is not touched or bruised by mechanical handling.

PRIORITY CLAIM

This application is a divisional of U.S. application Ser. No. 10/878,960filed on Jun. 28, 2004 entitled MACHINE FOR PRECISION LOW-STRESS CORINGAND SLICING OF APPLES AND OTHER SOFT-CORED OR PITTED FRUITS now U.S.Pat. No. 7,185,583, which application claims priority to U.S. Ser. No.60/482,982 entitled PREMIUM APPLE SLICING SYSTEM filed Jun. 27, 2003 andU.S. Ser. No. 60/574,348 entitled A SYSTEM AND METHOD FOR APPLE SLICINGAND A DOUBLE-SEALING TRAY filed May 25, 2004, all of which are herebyincorporated herein by reference in their entirety as if fully set forthherein.

FIELD OF THE INVENTION

An apple processing machine which cores and slices apples and other softfruits that are intended for fresh-slice consumption.

BACKGROUND OF THE INVENTION

Throughout history and prior to the mid 1990's, it was universallyrecognized that fresh sliced apple wedges would begin to turn brownwithin a few minutes of slicing. Consequently, fresh apples have alwaysbeen sold in whole form and sliced in the home or restaurant just beforeuse. The exceptions are the processors who slice apples for pie filling,dehydrated and canned fruit. Apples sliced toward these purposes do notrequire the scrutiny that a consumer would give to fresh-sliceconsumption. Consequently, the prior art of apple coring and slicing hasfocused on speed rather than accuracy, permitting “allowable” levels ofbruising, or otherwise damaging of the fruit. Near perfect slicing withlittle or no bruising was perceived as unnecessary.

Breakthroughs in enzyme research during the 1990's have produced asolution for keeping apple slices from turning brown. This has createdconsumer demand for sliced apples for fresh consumption and greaterconsumer scrutiny of the product. However, existing equipment can notmeet the demand for this higher level of apple-slice quality. Currentmachinery uses mechanical grippers, pins, conveyers, agitators and othersimilar means to orient apples, hold them during slicing or peeling,transfer them from station to station, and cut away at their seed podsand skins.

Although prior inventions have attempted to accomplish “carefulhandling” of fruit in the slicing process, they all fall short of theirobjectives. Examples are as follows:

1) Some prior art devices attempt to orient the apple using locators inthe blossom and stem holes, but thereafter transfer the apple throughsuccessive stations where that registration is lost. The stations wherethe “orientation” occurs are not the stations where the slicing andrelated processes occur; 2) Machines that mechanically remove the corefrom the middle of the apple fail to recognize that the core of theapple is not always in the geometric center of its equator, or in thecenter of gravity of the apple. The core is more typically in linebetween the stem hole and the calyx; but even then the axis formed bythe stem hole and calyx is often enough not an axis through the centerof gravity of the apple. As a result of these problems, the prior artmachines do not consistently and accurately remove the entire core witha minimum of damage and lost fruit; 3) Prior devices “grab” or grasp theoutside of the apple mechanically, which bruises the apple, causingdiscoloration, change of flavor and more rapid decay. Bruises frompressure will turn brown even with enzyme treatment; 4) Nibbling away atthe core or trepanning or machining or spiral cutting the core of theapple causes abrasion which also causes browning in spite of enzymetreatment; and 5) Any tearing action (as opposed to cutting) breaks upthe cell structure of the apple meat and causes browning and unsightlyand unappetizing rough surfaces.

SUMMARY OF THE INVENTION

The preferred embodiment of the present invention relates to solving theforegoing and related problems. The preferred embodiment of the presentinvention relates to a solution to creating fresh apple slices withlittle or no deterioration and discoloration. The preferred embodimentof the present invention comprises features that previously have neverbeen addressed: avoiding the need for mechanical “gripping” on theoutside of the fruit; holding the apple by the core during coring andslicing; holding the travel path of the apple straight as the applepasses through the slicing blades; piercing the core and isolating it,not spiral cutting the core away as debris; and locating, coring andslicing all in one station and/or in one continuous movement.

Objects And Features Of The Preferred Embodiment Of The Invention

One principal objective of the preferred embodiment of this invention isto core and slice apple wedges for fresh-slice consumption, byminimizing mechanical stresses on the apple during processing and byeffecting straight and precise cuts through the apple with little or notearing of the apple's cell structure.

An object of the preferred embodiment of this invention is to hold theapple by the core, using a compressive force applied betweentwin-opposed coaxial pins that are positioned into the calyx and thestem hole, the force being sufficient to retain the core after theedible portion of the apple is removed.

Another objective of the preferred embodiment of this invention is toaccurately locate the core and seedpod of the apple and to remove themin solid form without creating debris.

Another objective of the preferred embodiment of this invention is tohold the apple by the core, in order to eliminate machine contact withthe outer skin of the edible part of the apple, thereby preventinggrasping, pinching, impacting or similar pressures that would otherwisebruise the edible portion of the apple.

Another objective of the preferred embodiment of this invention is toprovide for human discretion in the placement and orientation of theapple before coring and slicing.

Another objective of the preferred embodiment of this invention is tohold the apple by the aforementioned pins and to shape the contactsurfaces to fit the apple's contour in those regions, thus maximizingtheir area of contact.

Another objective of the preferred embodiment of this invention is tohold the core of the apple between the aforementioned pins with apressure that can be adjusted to accommodate the characteristics ofdifferent varieties of fruit, their hardness, pressure and othercharacteristics that affect the general strength of the fruit duringprocessing.

Another objective of the preferred embodiment of this invention is toprovide a straight and continuous guide path of apple movement byaligning the concentricity of guide pins, core tube and ram.

Another objective of the preferred embodiment of this invention is toprovide a straight and continuous guide path for the apple's movement byrequiring the outside diameters of the core tube and lower guide pin tobe effectively the same diameter, same shape, same surface finish andjoined “in line, end to end” during slicing.

Another objective of the preferred embodiment of this invention is topierce the core of the apple with a thin-walled core tube, to minimizefriction and displacement of the apple's cell structure during coring.

An object of the preferred embodiment of this invention is to create asolid core that is retained during the slicing motion and ejectedseparately thereafter.

Another object of the preferred embodiment of this invention is todirectly slice wedges in a downward motion immediately into an enzymeemersion without delays that would permit oxygen degradation of thefresh-cut apple surfaces.

Another object of the preferred embodiment of this invention is toseparate the sliced wedges during their descent through the slicingblades such that they fall into enzyme emersion as individual segments,thus assuring complete enzyme coating of the all sliced surfaces.

Another object of the preferred embodiment of this invention is toprovide a modular design to the machine which allows for variable sizesof guide pins and core tubes, suitable for various sizes of apples,recognizing that larger apples have larger core and seedpod areas,requiring larger core tubes and guide pins.

Objectives with Regard to the Equipment, Its Safety, Productivity,Useful Life, and Efficient Operation

Another principal object of the preferred embodiment of this inventionis to automate the apple coring and slicing operation for the sake ofproduct quality, food safety and production efficiency.

An objective of the preferred embodiment of this invention is to balancethe center of gravity and the center of all forces in the machinery,using a radial design such that all forces are at equilibrium in thegeometric center of the machine.

An objective of the preferred embodiment of this invention is to usecompatible materials which may be similar or dissimilar depending ontheir requirements for strength, wear, rigidity, natural lubricity,induced or reduced friction and non-corrosive applications, recognizingthat the invention must meet the material requirements for food safetyapplications.

An objective of the preferred embodiment of this invention is an “openarchitectural design” that permits easy cleaning, easy disassembly andreplacement of components and reassembly of the equipment.

An objective of the preferred embodiment of this invention is to performin an automated continuous duty cycle for long periods of time.

An objective of the preferred embodiment of this invention is to provideinfinite speed, pressure and time delay adjustability, any combinationof which can be suited to the product and operator's requirements.

An objective of the preferred embodiment of this invention is to allowhuman discretion in the apple selection and placement process at thepoint of insertion of the apple.

The foregoing objects, and how they are accomplished by one or morefeatures of the preferred embodiment of the invention are more fullydescribed below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts an overview of the preferred embodiment of the invention.

FIG. 2 depicts only a portion of the preferred embodiment, for clarity,with all the other parts from FIG. 1 not shown. Specifically, FIG. 2only shows: apple (1), upper guide pin (2), core tube (3), rubber-facedram (4), lower guide pin (5), and knife cassette (6).

FIG. 3 depicts the Blade Cartridge Assembly.

FIGS. 4 a, 4 b, 4 c and 4 d each depicts sectional views of a portion ofthe preferred embodiment in operation.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to FIG. 1, the preferred embodiment of this invention isimplemented by a machine supported by three legs (8) inside a reservoirof enzyme solution (not shown). The level of solution approaches theheight of the lower platform (9). Apples (1) that pass through the knifecassette (6) fall immediately into the solution. Integral to the knifecassette is a vertical lower guide pin (5) that is an extension of theblade cone support (7). The bottom of the blade cone support rests onthe same plane as the bottom of the legs.

For clarity, FIG. 2 shows only apple (1), upper guide pin (2), core tube(3), rubber-faced ram (4), lower guide pin (5), and knife cassette (6)with all the other parts from FIG. 1 not shown. Rubber-faced ram (4)need not be covered with rubber, but can be uncovered, or covered withother cushioning, flexible or elastic type material.

Referring now briefly to FIG. 3, the blade cartridge assembly iscomprised of the lower guide pin (5), knife cassette (6) (from FIG. 2),and blade support cone (7). The blade cartridge assembly can be removedand replaced at will by lifting it out of position. FIG. 3 also depictsblade ring (17) with blade locking wedges (18). The head of the lowerguide pin (5) is the target for apple placement. An apple (1) may beplaced to rest on its calyx, or it may be placed upside-down or invertedto rest on its stem hole, either being at the discretion of the operatorbased on the shape of the variety of apples being processed.

The knife cassette (6) (from FIG. 2, but shown in constituent parts inFIG. 3) holds a plurality of vertical blades (19). There may be as fewas one or two blades cutting the apple into two sections, or as manyblades desired to cut any maximum discrete number of segments. Theblades radiate outwardly from the lower guide pin (5) to the outer ringof the blade cartridge assembly (see FIG. 3). Although the direction ofslicing is vertical, the blades are tipped downward toward the lowerguide pin (6) and its blade support cone (7). Thus, a bias in applemotion is created which naturally holds the wedges against the lowerguide pin's outer surface until the blade support cone (7) spreads thewedges outwardly into solution. Wedges move straight down during slicingand then outward into solution after slicing is complete.

Referring back to FIG. 1, a safety door (18) is timed to open and close,allowing the operator to place an apple (1) on the lower guide pin (5)and wait for the upper guide pin (2) to descend into place, at whichtime the operator pushes the cycle start button (17) to initiate thebalance of the cycle.

Continuing to refer to FIG. 1, in order to minimize the use ofelectricity in a wet area (a matter of safety), the operation of themachine is controlled by an air-logic system that distributes air atgiven pressures, intervals and directions, to a series of air cylinders(15) that are fixed to the upper platform (11). In the very center ofthe upper platform (11) is a single air cylinder that drives the upperguide pin (2). On opposing sides of the single air cylinder are twoadditional air cylinders that drive the coring platform (14). The coringtube (3) is fixed to the coring platform (14) and encapsulates the upperguide pin (2).

When the cycle start button (17) is pushed the coring tube (3) descends,pierces the apple, isolates the apple core internally and stops slightlyshort of contacting the lower guide pin (5). During the core tube'sdescent the apple (1) remains in place because it is attached to itscore all the way up to the final moment when the core tube piercesthrough the bottom of the apple. At that point the apple separates fromthe core, but remains suspended on the core tube (3) by friction.

Next, twin opposed air cylinders (15) mounted on the upper platform (11)(preferably in a transverse plane to the previously mentioned aircylinders) drive the ram platform (13). The rubber-faced ram (4) isfixed to the ram platform (13) and encapsulates the core tube (3). Theram (4) pushes the apple (1) downward. The apple (1) pilots itself in atelescoping fashion, firstly sliding over the core tube (2), andsecondly over the lower guide pin (5), making a seamless transitionbetween the two. Knife blades that extend radially from the lower guidepin (5) slice the apple into a plurality of segments or wedges whichfall into enzyme solution.

The frame of the machine is made up of two fixed triangular platforms,the lower platform (9) and the upper platform (11). They are spacedapart by three fixed ceramic coated guide rails (10), upon which allother platforms are free to move in the vertical direction by way ofcomposite bearings (12). The length of stroke for each platform isadjustable by means of stop nuts (16) at the top of cylinder rods and bythe use of spacers (not identified in this FIG. 1).

After the apple is sliced, the ram (4), core tube (3) and the upperguide pin (2) are retracted in sequence to their uppermost positions. Asthe core tube (3) retracts it exposes the solid core of the apple. Atthis point the core is still being held by pressure between the lowerguide pin (5) and upper guide pin (2). At the moment that pressure isreleased, a transverse air blast ejects the solid apple core into aseparate receptacle. Finally, the safety door opens, the operator placesanother apple and the cycle repeats.

FIG. 3—Blade Cartridge Assembly. The blade cartridge assembly is aseparate serviceable unit of the coring and slicing machine. It can bequickly disassembled, serviced and reinstalled. The blade support cone(7) is the base unit that rests on the bottom tray surface of an enzymereservoir. It is normally submersed in the enzyme solution. The blademandrel (20) is directly above the blade support cone (7) and isfastened into it. Individual knife blades (19) are embedded into theblade mandrel (20) and clamped downward by the lower guide pin (5). Theblade cartridge assembly holds a plurality of knife blades that extendradially from the blade mandrel (20) and terminate in slotted positionsin the blade ring (17). The knife blades (19) are individually clampedto the blade ring (17) with blade locking wedges (18). The diameter ofthe blade mandrel (20) is less than the lower guide pin (5). Thiscondition permits the knife blades (5) to be anchored and restrainedbelow the lower guide pin (5) and inside the perimeter of the guidepin's sliding diameter such that the active cutting edges of the knifeblades will completely sever the apple segments from lower guide pin (5)to blade ring (17) without any obstructions, spot welds, bends, or otherinterruptions to the cutting surfaces. The blade locking wedges (18)exert a side pressure against the knife blades (19) that assures theirrigid vertical position during slicing. The knife blades (19) areradially positioned in a downward direction from the outer blade ring(17) to inner lower guide pin (5). This condition creates a bias inapple wedge motion, such that the wedges are held against the lowerguide pin's (5) outer surface as they descend through the knife blades(19). This assures a straight path through the knife blades (19) duringslicing which prevents tearing of the apple's cell structure. At thebottom of the descent the tapered apron surface of the blade supportcone (7) spreads the apple wedges in an outward direction so that theywill fall into the enzyme individually and be fully coated with enzyme.

Referring now to FIG. 4, the operation of the preferred embodiment canbe better understood. In FIG. 4-a, apples (1) are positioned by humandiscretion and oriented by hand so that the calyx of the apple rests ona vertical lower guide pin (5). Concurrently, as part of an automatedcycle, an upper guide pin (2), coaxial with the lower guide pin (5),descends into the stem hole until a preset pressure between pins securesthe apple in a stationary position, held by a compressive force throughits core, as shown in FIG. 4-a.

As shown in FIG. 4-b, the operator's hand is removed and the cyclecontinues such that a thin-walled coring tube (3) descends downward,piloting over the upper guide pin (2) and through the apple (1) in apiercing motion until it reaches the lower guide pin (5), thusseparating the core of the apple from the rest of the apple, internally,as shown in FIG. 4-b. Thereafter, a soft rubber faced ram (4) descendsdownward, piloting over the core tube (3) as it pushes the apple througha cassette of radial knife blades (6) so as to create a plurality ofwedges in a single descent. The apple is guided through its descent,first over the core tube (3), and secondly over the lower guide pin (5).A tapered support pillar under the knives induces the wedges to separatefrom each other as they descend into a solution of enzymes thatimmediately seal freshness into the apple by preventing oxygen fromreaching or reacting with the raw cell structure of the sliced wedges,as shown in FIG. 4 c.

Thereafter, the ram (2), core tube (3) and upper guide pin (4) retractto their upper positions allowing the solid apple core to be ejected ata precise moment by air blast or other method, as shown in FIG. 4 d. Atthis point the operator is ready to place another apple and the cyclerepeats.

SUMMARY OF THE PREFERRED EMBODIMENT

In the preferred embodiment a single station is used to position theapple, to compress and hold the apple by its core, to core (pierce andisolate) the apple, to slice the apple, and to retain and eject thesolid core. In other words, instead of grasping the apple and slicingand punching out the core, this embodiment captures the core, and slicesoff the apple in slices. The apple slices have but to fall away from theblades into the solution without being handled at all. This embodimentproduces the most accurate and premium quality product and substantiallyreduces the cost of equipment. The outside surfaces of the edibleportion of the apple (the slices themselves) are not touched by machinecomponents, and are therefore not bruised or otherwise damaged. The cutsurfaces are straight and cleanly severed with little or no tearing ofthe apple's cell structure. The above accuracy of slicing is facilitatedby combining the core tube (3) and lower guide pin (5) into a concentricand connected condition that creates a continuous and seamless “linearguide rail”. The apple (1) is piloted through the knives over this“combined linear rail”, assuring a precision low stress coring andslicing of the apple.

DESCRIPTION OF SOME ALTERNATE EMBODIMENTS

It is possible to divide the process steps described in the “singlestation” embodiment discussed above into a “multiple station” conceptwithout compromising the claims of the invention or merits of theprocess as claimed. One example would be to create a “two station”machine with a circular turret concept. Apples would be loaded intostation #1 where they would be oriented and cored, then the turret wouldindex so that the upper half of the machine would take the cored apple(still around the core tube) to a second station. At station #2 thealready cored apple would be sliced by the same ram movement discussedabove. The core could be ejected at station #1 or station #2 aspreferred. This embodiment would reduce the cycle time of the machineand increase production. It would require two identical “pin, tube &ram” assemblies that would index above the apple, between station #1 andstation #2. Station #1 would house a lower guide pin only. Station #2would house a complete blade cartridge assembly with lower guide pin.All of the described conditions of alignment, concentricity, and contactwould be maintained at each station, just as they are in the “singlestation” preferred embodiment.

Likewise, “twin-spindle” configurations could also index throughmultiple stations, thereby processing more than one apple at a time. Inother embodiments, one or more of the features described above could becombined with the “twin-spindle” embodiment.

In alternate embodiments, some or all of the actions attributed to thehuman operator can be performed automatically, by machine, orrobotically, and/or in response to computer programmed instructions.

In addition to “apples”, other relatively soft-cored fruits such asAsian, or other pears are equally served with the preferred embodimentor other embodiments of this invention.

In addition to soft-cored fruits, pitted fruits such as apricots andpeaches are equally served with the preferred embodiment or otherembodiments, understanding that the core tube is preferably greater indiameter than the pit of the fruit.

In addition to soft-cored fruits and pitted fruits, fibrous cored fruitssuch as pineapples may be sliced in similar format by the preferredembodiment other embodiments, understanding that a generally largerscaled machine size is preferable.

1. A method to core pitted fruit or soft-cored fruit to remove a fruitpit or a soft core from fruit meat and to slice fruit meat comprising:holding the pitted fruit or the soft-cored fruit between a first pin anda second pin, the first pin and the second pin being linearly opposedalong a common axis; pressing a core tube concentric with the first pinand the second pin through the held pitted fruit or the soft-cored fruitto capture the fruit pit or soft core within the internal region of thecore tube while the fruit meat adheres to the external surface of thecore tube; moving the adhered fruit meat from the external surface ofthe core tube and through a plurality of blades outwardly radiatingbeneath the second pin; expelling slices of the fruit meat into areservoir beneath the plurality of blades upon passage of the adheringfruit meat through the plurality of blades; and ejecting the fruit pitor the soft core from the internal region of the core tube duringmovement of the adhering fruit meat into a separate receptacle.
 2. Themethod of claim 1, wherein holding the pitted fruit or the soft-coredfruit includes placing the calyx of the pitted fruit adjacent to thesecond pin or placing the stem hole of the pitted fruit adjacent to thesecond pin.
 3. The method of claim 1, wherein pressing the core tubeincludes transiting through the pitted fruit or the soft-cored fruitwithout completely penetrating through the pitted fruit or thesoft-cored fruit near the second pin.
 4. The method of claim 1, whereinexpelling slices of the fruit meat into the reservoir includes engaginga conical shaped pillar support to separate the slices within thereservoir having an enzyme solution formulated to minimize oxidation ofthe slices.
 5. The method of claim 1, wherein ejecting the fruit pit orthe soft core includes purging the fruit pit or the soft core from thecore tube to the separate receptacle using pressurized gases directedtransversely to the core tube.
 6. The method of claim 1, wherein thepressing, moving, expelling, and ejecting sequence is controlled by anair-logic system that distributes air at given pressures, interval, anddirections to initiate the sequence after placing the pitted fruit orthe soft-cored fruit between the first pin and the second pin.